Factor 4x^2-4

$4 x^{2} - 4$

Step 1

Factor $4$ out of $4 x^{2} - 4$ .

Factor $4$ out of $4 x^{2}$ .

$4 (x^{2}) - 4$

Factor $4$ out of $- 4$ .

$4 (x^{2}) + 4 (- 1)$

Factor $4$ out of $4 (x^{2}) + 4 (- 1)$ .

$4 (x^{2} - 1)$

Step 2

Rewrite $1$ as $1^{2}$ .

$4 (x^{2} - 1^{2})$

Step 3

Factor.

Since both terms are perfect squares, factor using the difference of squares formula, $a^{2} - b^{2} = (a + b) (a - b)$ where $a = x$ and $b = 1$ .

$4 ((x + 1) (x - 1))$

Remove unnecessary parentheses.

$4 (x + 1) (x - 1)$